Shopping for a PDF API means comparing three things that vendors rarely put side by side: the rendering engine (what your CSS will actually look like), the pricing unit (documents, credits, or megabytes), and everything around the conversion — retries, webhooks, storage, compliance. Here's the landscape as of publication; prices come from each vendor's public pages and are worth re-checking.
The contenders at a glance
DocRaptor renders with Prince XML, widely regarded as the gold standard for print-grade CSS (running headers, footnotes, page floats). Listed plans start free at 5 documents/month, then from $15/month for 125 documents. If you're producing a book or a regulator-grade report, Prince's print fidelity is the argument. The trade: per-document cost rises quickly, and it's conversion-only — no extraction, OCR or editing.
PDFShift is Chromium-based — your PDF matches Chrome — with a listed free tier of 50 credits/month and paid plans from $9/month. Lean, developer-friendly, single-purpose: HTML to PDF is the product. If that's your entire need, it's efficient; anything else (merge, OCR, data extraction) means a second vendor.
Api2Pdf is the budget engine room: usage-based pricing with no monthly minimum, fractions of a cent per PDF, and a choice of wkhtmltopdf, Chrome or LibreOffice under the hood. Excellent for spiky or low volume. The trade-offs: you pick engines yourself, and the platform layer (workflows, retention controls, extraction) is thin.
ASHDOCS is the suite play: 24 tools behind one key — HTML/URL/Office/image/Markdown conversion, merge/split/compress/watermark editing, AES-256 protection and true redaction, OCR and schema-driven extraction to JSON, bank statements to CSV/QBO, PDF to Markdown for RAG pipelines. Free tier: 100 credits/month; Starter $19/month for 1,000 credits (1 credit = 1 successful conversion; failed jobs uncharged; sandbox keys never bill). Rendering is Chromium-class, so HTML fidelity matches PDFShift's class rather than Prince's print-typography class.
How to choose
Print-perfect typography (books, complex paged media): DocRaptor — Prince XML is genuinely better at this.
Only HTML to PDF, minimal footprint: PDFShift or Api2Pdf, decided by whether you prefer subscription or pure usage billing.
Spiky workloads, minimum spend: Api2Pdf's no-minimum model is hard to beat.
More than conversion — you also extract data, OCR scans, redact PII, or feed LLM pipelines: a suite beats stitching three vendors. One key, one invoice, one webhook format is the actual feature.
No-code pipelines (Make, Zapier, n8n): check what each vendor documents; ASHDOCS treats the no-code path as a first-class citizen with REST endpoints designed for HTTP modules.
The pricing-unit trap
"From $9" and "from $15" hide the real comparison: cost per document at your volume and file size. PDFShift credits scale with file size; DocRaptor counts documents; Api2Pdf bills usage; ASHDOCS charges flat credits per successful operation. Model a month of your actual traffic before deciding — the cheapest headline is frequently not the cheapest invoice.
FAQ
What's the best DocRaptor alternative? Depends on why you're leaving. For price at Chromium-fidelity: PDFShift, Api2Pdf or ASHDOCS. For breadth beyond conversion: a suite like ASHDOCS. If you rely on Prince-specific paged-media CSS, budget porting time.
Which PDF APIs have free tiers? All four discussed here: DocRaptor 5 docs/month, PDFShift 50 credits/month, ASHDOCS 100 credits/month, and Api2Pdf simply bills usage from zero. (Listed figures at publication; verify.)
Do any handle data extraction, not just generation? Of these four, only ASHDOCS — tables to CSV/XLSX, schema-driven PDF-to-JSON with confidence scores, OCR, and bank-statement parsing.
Chromium or Prince — which engine do I want? Chromium for "make it look like my web page." Prince for "make it look like a typeset book." Most SaaS documents want the former.
Run the comparison yourself — 100 free credits, no card.